1. Field of the Invention
The present invention relates to rubber compositions and more particularly to a rubber composition having excellent moisture resisting adhesion and capable of preventing a decrease in the strength of adhesion with brass plate cords when exposed to high humidity.
2. Prior Art
Conventionally, as a means to improve the performance of an automobile tire, belt conveyor, etc., steel cords plated with brass have been widely used as a reinforcement. Also, composites for improving the adhesive property are compounded from one or more types of bonding agents selected according to requirements from the group consisting of resorcin, resorcin-formaldehyde resin, hexamethylenetetramine, melamine derivative, cobalt salt, etc., with various types of rubber composites have been known. These conventional rubber composites for steel cords, however, were disadvantages in that when exposed to high humidity, the rubber absorbs moisture, and particularly in an ambient temperature above 40.degree. C. and a relative humidity at above 90 percent, the absorption of moisture by the rubber becomes substantially large. The absorption of moisture in the rubber causes an adverse effect on the interface of the adhesion between the steel cords and the rubber to allow the steel cord to separate from the rubber resulting in a shortened life for the product.